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Difference between Destroy and Delete
...ary key, and no callbacks are executed.
To enforce the object's before_destroy and after_destroy callbacks or any :dependent association options, use #destroy.
ActiveRecord::Persistence.destroy
Deletes the record in the database and freezes this instance to reflect that no changes should b...
How do I create a new Swift project without using Storyboards?
..., UIApplicationDelegate {
var window: UIWindow?
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey : Any]? = nil) -> Bool {
window = UIWindow(frame: UIScreen.main.bounds)
if let window = window {
...
Generating Random Passwords
...Define default min and max password lengths.
private static int DEFAULT_MIN_PASSWORD_LENGTH = 8;
private static int DEFAULT_MAX_PASSWORD_LENGTH = 10;
// Define supported password characters divided into groups.
// You can add (or remove) characters to (from) these groups.
priv...
How do I delete an exported environment variable?
Before installing gnuplot, I set the environment variable GNUPLOT_DRIVER_DIR = /home/gnuplot/build/src . During the installation, something went wrong.
...
Easily measure elapsed time
...
//***C++11 Style:***
#include <chrono>
std::chrono::steady_clock::time_point begin = std::chrono::steady_clock::now();
std::chrono::steady_clock::time_point end = std::chrono::steady_clock::now();
std::cout << "Time difference = " << std::chrono::duration_cast<std::c...
“open/close” SqlConnection or keep open?
...ion()) {} public SqlConnection GetConnection() { return new SqlConnection(_connectionString); }
– ganders
Jan 23 at 17:12
...
Using PowerShell to write a file in UTF-8 without the BOM
...ry {
$Input | Out-String -Stream @htOutStringArgs | % { $sw.WriteLine($_) }
} finally {
$sw.Dispose()
}
}
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Is it possible to break a long line to multiple lines in Python [duplicate]
... line
appropriately.
Example of implicit line continuation:
a = some_function(
'1' + '2' + '3' - '4')
On the topic of line-breaks around a binary operator, it goes on to say:-
For decades the recommended style was to break after binary operators.
But this can hurt readability in t...
Android Facebook integration with invalid key hash
... "com.example.packagename",
PackageManager.GET_SIGNATURES);
for (Signature signature : info.signatures) {
MessageDigest md = MessageDigest.getInstance("SHA");
md.update(signature.toByteArray());
Log.d("KeyHash:", Base64.encodeToString(md.diges...
Using the “animated circle” in an ImageView while loading stuff
...:
<RelativeLayout
android:id="@+id/loadingPanel"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center" >
<ProgressBar
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:in...